From arm wrestling gone wrong to flying pocket knives, district health boards have reported on "adverse events" affecting 525 patients in the year to June.
This is 16 per cent more than the 454 national adverse events in 2013/14, according to data collated by the Health Quality and Safety Commission, which says the increase is probably due to better reporting.
Seventy-three of the patients in the latest annual tally died, although not necessarily because of the adverse event.
Falls causing serious harm were again the most commonly reported event, accounting for 277 cases, followed by 205 cases attributed to problems with clinical management which included misdiagnosis, failure to act on lung x-ray abnormalities that turned out to be cancer, delays in treatment, misinterpretation of electronic fetal monitoring in labour, and leaving swabs and instruments in patients.
An adverse event is defined as one that causes serious harm or death, or could have done so.